Additional information concerning
XMM-Newton data files can be found in the Interface
Control Document: Observation and Slew Data Files (XSCS to SSC)
(SciSIM to SOCSIM) (XMM-SOC-ICD-0004-SSD). This is an
impressive tome which goes into great detail about the file
nomenclature and structure. This document can be found in the
documents area of the SOC web pages:
http://xmm.esac.esa.int/.

5.2 The Data

One of the first steps that should be taken when examining your data is to check to
see what you actually have. XMM-Newton observations can be broken into several exposures
which are each assigned separate observation numbers. These separate
exposures can be radically different in length and can also have the
different instruments in different modes. For example, in one case
the full observation was 60 ks with EPIC and RGS active but there was
one delivered exposure which was ks and had only RGS active.
(This can happen because the RGS can operate farther into regions of
higher radiation than the EPIC detector. The additional observation
time can be considered an additional exposure with only the RGS
active.) Two files are useful and should be downloaded to the user's
machine for this examination. First, the primary HTML page is
INDEX.HTM which is included in the Pipeline Products. This page
lists basic information for the observation plus the operational modes,
filters, and exposure start and stop times for the individual instruments.
It also has links to various summary pages, including those for the
instruments. (In the case above, the EPIC summary page simply stated that
``EPIC exposures processed by PPS None.'') Specifically, LOOK at the
P*SUMMAR0000.HTM files in the pipeline products (easily available
through the links). Second, to quickly access images from the various
instruments examine the PPSGRA Pipeline Products page
(§ 5.3.3).

5.3 PI Data

Proprietary XMM-Newton data is available for download via your
XSA account. Email instructions from the XMM-SOC at Vilspa are sent to
the address on record with detailed directions on how to retrieve your
data via the XSA.

XMM-Newton data is available for download at the HEASARC data archive.
The data files can be considered to come in two groups in separate
subdirectories when retrieved, the Observation Data Files (ODF) files
and Pipeline Processing (PPS) files. The ODF data contain all of the
observation-specific data necessary for reprocessing the observation.
The PPS data contain, among other things, calibrated photon event files
and source lists.

5.3.1 ODF Data

ODF data come with file names in the following format:

mmmm_iiiiiijjkk_aabeeeccfff.zzz

mmmm - revolution orbit number

iiiiii - proposal number

jj - target ID number in proposal

kk - exposure number for target

(NOTE: The ten-digit
combination of iiiiiijjkk is the observation number and is
used repetitively throughout the file nomenclature.)

b - flag for scheduled (S) or unscheduled (U) observations,
or X for general purpose files)

eee - exposure number

cc - CCD number or OM window number

fff - data identifier for the three detectors or spacecraft itself;
see Table 5.1.

zzz - format (FIT - FITS, ASC - ASCII)

Table 5.1:
ODF data file identifiers.

Data ID

Contents

EPIC files

IME

Event list for individual CCDs, imaging mode

RIE

Event list for individual CCDs, reduced imaging mode

CTE

Event list for individual CCDs, compressed timing mode

TIE

Event list for individual CCDs, timing mode

BUE

Event list for individual CCDs, burst mode

AUX

Auxiliary file

CCX

Counting cycle report (auxiliary file)

HBH

HBR buffer size, non-periodic housekeeping

HCH

HBR configuration, non-periodic housekeeping

HTH

HBR threshold values, non-periodic housekeeping

PEH

Periodic housekeeping

PTH

Bright pixel table, non-periodic housekeeping

DLI

Discarded lines data

PAH

Additional periodic housekeeping

PMH

Main periodic housekeeping

RGS files

AUX

on-board processing statistics

SPE

raw event list for one CCD

DII

diagnostic images

D1H

CCD readout settings

D2H

CCD readout settings

PFH

housekeeping data

ODX

pixel offset data

XMM files

ATS

spacecraft attitude history

OM files

IMI

imaging file

THX

tracking history file

WDX

window data auxiliary file

NPH

non-periodic housekeeping file

PEH

periodic housekeeping file

PAX

field acquisition data

RFX

priority reference frame data

PFX

priority fast mode data

FAE

event list (if fast mode was used)

5.3.2 Pipeline Product Data - Summary Files and Groupings

The Pipeline Processing (PP) produces quite a number of useful products which
allow a first look at the data, but can overwhelm the user by their sheer numbers.
The first place to look is the INDEX.HTM page which organizes the presentation of
the data and provides links to other PP pages. The INDEX.HTM page also lists general
observation information (target, date, time, etc.) and instrument modes.

The INDEX.HTM page provides links to various observation summary pages, which
have names with the following nomenclature:

PP data contain some immediately useful data products such as calibrated photon
event lists, source lists, and images. While there are a large number of
products which come in a single directory, they can be associated in up to
15 groupings; see Table 5.2. (The number of groups
can vary depending on the number of operational instruments, e.g., if the
OM is turned off there are no OM products.) Further information on each of these
groupings and associated files, such as file contents, file types, and how they
may be viewed, can be found in Table 5.3. Each group has an
associated HTML file which organizes access to the files and provides a
limited description of them. The names of the HTML files are of the
following form: